Journal article

Recurrent heterozygous PAX6 missense variants cause severe bilateral microphthalmia via predictable effects on DNA-protein interaction


Authors listWilliamson, Kathleen A.; Hall, H. Nikki; Owen, Liusaidh J.; Livesey, Benjamin J.; Hanson, Isabel M.; Adams, G. G. W.; Bodek, Simon; Calvas, Patrick; Castle, Bruce; Clarke, Michael; Deng, Alexander T.; Edery, Patrick; Fisher, Richard; Gillessen-Kaesbach, Gabriele; Heon, Elise; Hurst, Jane; Josifova, Dragana; Lorenz, Birgit; McKee, Shane; Meire, Francoise; Moore, Anthony T.; Parker, Michael; Reiff, Charlotte M.; Self, Jay; Tobias, Edward S.; Verheij, Joke B. G. M.; Willems, Marjolaine; Williams, Denise; van Heyningen, Veronica; Marsh, Joseph A.; FitzPatrick, David R.

Publication year2020

Pages598-609

JournalGenetics in Medicine

Volume number22

Issue number3

ISSN1098-3600

eISSN1530-0366

Open access statusHybrid

DOI Linkhttps://doi.org/10.1038/s41436-019-0685-9

PublisherElsevier


Abstract
Purpose Most classical aniridia is caused by PAX6 haploinsufficiency. PAX6 missense variants can be hypomorphic or mimic haploinsufficiency. We hypothesized that missense variants also cause previously undescribed disease by altering the affinity and/or specificity of PAX6 genomic interactions. Methods We screened PAX6 in 372 individuals with bilateral microphthalmia, anophthalmia, or coloboma (MAC) from the Medical Research Council Human Genetics Unit eye malformation cohort (HGU(eye)) and reviewed data from the Deciphering Developmental Disorders study. We performed cluster analysis on PAX6-associated ocular phenotypes by variant type and molecular modeling of the structural impact of 86 different PAX6 causative missense variants. Results Eight different PAX6 missense variants were identified in 17 individuals (15 families) with MAC, accounting for 4% (15/372) of our cohort. Seven altered the paired domain (p.[Arg26Gln]x1, p.[Gly36Val]x1, p.[Arg38Trp]x2, p.[Arg38Gln]x1, p.[Gly51Arg]x2, p.[Ser54Arg]x2, p.[Asn124Lys]x5) and one the homeodomain (p.[Asn260Tyr]x1). p.Ser54Arg and p.Asn124Lys were exclusively associated with severe bilateral microphthalmia. MAC-associated variants were predicted to alter but not ablate DNA interaction, consistent with the electrophoretic mobility shifts observed using mutant paired domains with well-characterized PAX6-binding sites. We found no strong evidence for novel PAX6-associated extraocular disease. Conclusion Altering the affinity and specificity of PAX6-binding genome-wide provides a plausible mechanism for the worse-than-null effects of MAC-associated missense variants.



Citation Styles

Harvard Citation styleWilliamson, K., Hall, H., Owen, L., Livesey, B., Hanson, I., Adams, G., et al. (2020) Recurrent heterozygous PAX6 missense variants cause severe bilateral microphthalmia via predictable effects on DNA-protein interaction, Genetics in Medicine, 22(3), pp. 598-609. https://doi.org/10.1038/s41436-019-0685-9

APA Citation styleWilliamson, K., Hall, H., Owen, L., Livesey, B., Hanson, I., Adams, G., Bodek, S., Calvas, P., Castle, B., Clarke, M., Deng, A., Edery, P., Fisher, R., Gillessen-Kaesbach, G., Heon, E., Hurst, J., Josifova, D., Lorenz, B., McKee, S., ...FitzPatrick, D. (2020). Recurrent heterozygous PAX6 missense variants cause severe bilateral microphthalmia via predictable effects on DNA-protein interaction. Genetics in Medicine. 22(3), 598-609. https://doi.org/10.1038/s41436-019-0685-9



Keywords


ANIRIDIAANOPHTHALMIAHOMEODOMAINMALFORMATIONSMICROPHTHALMIAmissense variantpaired domainprotein destabilizationSOX2

Last updated on 2025-10-06 at 11:09